The major limitations with the Mako are:
1) the 180' depth limit on the hull, and indirectly, the fairly fragile construction of the o-ring grooves in the nose cone/mid body and mid body/motor compartment junctions, and
2) the generally poor (tail low) trim attitude.
The 180' depth limit is also optimistic as they have a bad habit of imploding at about 130-140' with the stock nose plate. DPV repair sells a 3/4" lexan nose plate and I highly recommend it. With that plate, I'd consider 180' realistic and 200' do-able.
But, they are still a great introductory scooter and sell for a lot less than any other tech capable scooter out there.
Batteries are all over the map on the Makos. I prefer a pair of 12v Powersonic PSH-12180FR wired in series - about $60 each on line) but they are heavier and will require a neoprene sleeve (from DPV repair) to achieve neutral buoyancy in fresh water. They are the high current version of the 18 Ah Powersonic and seem to work better with higher RPM motors. The neoprene sleeve is a good idea anyway as it protects the o-ring grooves.
On our last cave trip we averaged 35-40 minutes of trigger time per dive, with 2 dives per charge, with the prop set on pitch 6 or 7 and the data loggers showed no more than 12,000 mAh used on any dive day. Target cruise speed in the caves was 150 fpm (in side mounted doubles and at times a stage) and the time/speed/distance calculations along marks lines was very close to the 150 fpm target.
Consequently, I like the batteries we use due to the burn time and available reserve, but with lighter batteries, in salt water and with the sleeve, you'll need 4-6 pounds of ballast in the nose cone and if you put it all the way forward, you can get the scooter to trim nearly level. In fresh water you can come close, but won't be able to carry quite enough ballast to make it happen. The batteries are also fairly easy to change, and being inexpensive ($120 per set) you can swap them out between dives and get either an 80-90 minute run time at reasonable speeds, or run them at pitch 9 and get 50-55 minutes of burn time. (I would not run them above that pitch on non stopped hubs as it causes the motor to overheat on runs over about 30 minutes.
Mako motors are also all over the board in terms of performance. The stock motors seem to vary from 600 to 750 RPM and the newer scooters/motors seem to be slower. Some have also been modified with 1000 rpm motors along the lines of what is used in SS and Gavin scooters. And with that mod, they offer similar speed.
Based on our experience, a 1000 rpm Mako with 12 ga wiring, 21 Ah batteries, 50 amp Anderson connectors and a prop hub without a pitch stop (allowing what amounts to an "11" pitch on a otherwise 1-9 pitch hub) will give about 200 fpm for a diver in doubles. A stock Mako with anemic 600-650 ish motor, 14 ga wiring, stock connectors and a stock prop hub will produce maybe 140 fpm on pitch 9. As noted above we get 150 fpm with pitch settings of 6 or 7 on our 1000 rpm Makos.
The bad news is that it is not economically sound to buy a used mako and then rewind the motor, replace the batteries, connectors, nose plate, rewind the motor, etc, as by the time you do all that, you could have bought a UV 18 or UV 26 for not much more money and have similar performance with more depth capability, better trim and no fragile o-ring groove issues. But if you already own one, it's something to consider.
The good news is that a modified Mako along those lines won't sell for much more than a stock Mako. So for $200-$300 more, you can get a Mako that will offer noticeably better performance.
Especially on long runs...
