nfarrar,
I have recently gone through the process of purchasing the exact set up you are talking about. I went with the Hollis Solo with 25lb single tank wing (and dive rite single tank adapter) , and 45lb double tank wing. Dive Rite Trans ended up last on my list because of all the plastic, it was more BC than BP/Wing.
I made some comments on a similar thread you might find interesting here's the link.
http://www.scubaboard.com/forums/cave-diving/400147-rookie-curiosity-here-6.html#post6159592
now to take part of what I said from the other thread
" 5. I agree with the DSS BP&W if I could have afforded it I would have gone that path, but due to limited finances I didn't. After research and chats with my instructor I considered DSS, Hollis, DiveRite Transplate, HOG, Halcyon, Aqua Mundo and a couple others. Prices are all similar (DSS is more expensive but your paying for service and quality). I'm 6 ft, 180 lbs, I ended up going with my second choice (after DSS) a Hollis setup 25lb Single wing, and a 45 lb double, my research, shop help and my instructor said it would be more than enough for what I want to do. If you go DSS Tobin sort you out.
Gear wise do some research on prices etc (try Dive Gear Express to check out prices, whether you shop there or not it's great website). From what I see most dedicated Tech divers seem to collect lots of gear over time so I'm sure I'll get to use DSS yet!
Think about whether you'll be traveling with gear. This is a consideration for BP material ie DSS Kydex Hybrid, Aluminum or Stainless Steel.
6.If you buy a BP&W you will probably get some form of pockets (BC's have pockets, BP&W usually don't) see the Hogarthian section for a thread on this Consider getting a single tank adaptor (possibly), and I would look at getting a Hogarthian harness, forget all the harnesses with plastic clips and do dad's. Personal opinion but I think a lot of people here would agree. See the discussion above about entanglement, streamline etc. If you seriously see your self going down the tech path, definite consideration. "
When I selected my gear 6 months ago I knew I was going to pursue tech diving. With help from my tech instructor I did lots of research See the other thread) I looked at the Transpac I didn't like the harness to much crap on it, like the Hollis elite range. I have to say I think those harnesses are produced to cure the divers who want a tech brand harness and back plate and are "hogarthian curious" and not able to give up on the ultra cool plastic BC look that dive manufactures brain wash the diving hordes with
(just an opinion please don't diverge on the thread to argue this) .
What people are saying above is true. Having used a single piece hogarthian back plate strap, I'll never go back. Having put 50 or so dives on the new gear and done some basic tech courses, I can't fault the setup, actually I LOVE IT. The cool thing about the solo harness is if you want more D-rings buy them and put them on. HOWEVER that said you'll quickly work out 2 on each shoulder, one on each hip and one on the front and rear of the groin strap will be more than you'll even need. The Hollis solo set up comes with 2 shoulder pads that you thread on to the harness . But after diving the gear I don't think I'd miss them but they look nice. You'd be amazed how many times people on boats look at your gear and go wow because of the simplicity, more than one person asked where they could get one
. Despite looking a bit uncomfortable before you try it, BP/Wing set ups are extremely comfortable, underwater. They give you a freedom of movement you won't find in a BC.
I went with Hollis for several reasons : Recommendation, personal research, Tech Instructor assistance ( he looked at my 3 favorite options), price (what I really wanted was slightly out of my price range - DSS). Keep in mind I had to order over the internet as where I live there are no shops or displays.
If you go with Dive Rite go with the basic harness (my opinion forget the deluxe and quick release) see below:
Backplate, Harness and Wing Systems (BPW) by Dive Rite - Dive Gear Express
Similar Hollis set up is here:
Backplate, Harness and Wing Systems (BPW) by Hollis - Dive Gear Express
Some other points:
I travel I went with aluminium. SS wasn't an option because of this.
Yes you will need 2 different wings one for doubles, one for singles. I would defer to coolhardware52 (Tobin from DSS I believe) here, this is his bread and butter. Personally I went with 25lb single, 45lb double based on instructor recommendation. Your 270lbs, I'm 180 ish pounds, I'm not sure how that will affect you. Keep in mind in warm salt water, I was diving a 3m wetsuit with 2 kg (4lb) of weight for trim and barely had any air in the wing, so there was still massive lift capacity and I was actually to lite!
Sorry for the long explaination, you did ask for opinion! I will point out I am new (less than 200 dives) compared to many of the respected posters above, but we're all singing from the same prayer book.
All the best, good luck!