I have mixed feelings and it depends on the conditions
1. In large deep lakes late in the summer with several thermoclines from derhaps 65-70 degree water on the surface to 35-39 degree water on the bottom, I actually prefer a semi-dry. On a moderate run time deep dive where half the dive is deco, a dry suit warm enough to keep you toasty on the bottom, will be uncomfortably warm at the 20' and 10' stops. With a semi dry you feel the cold a bit at the bottom but quickly warm up in the warmer layers, and if you get too hot at the shallow stops, you can flush some water through the suit - not an option with a dry suit.
2. Early or late in the season where there is less temperature differential and surface temps of only 50-60 degrees with the same 35-39 degree bottom temps, a dry suit is nice to have.
I also agree spending big bucks on a SP suit is perhaps not money well spent. Not much more money (around $500) will get you a 7/5mm O'Neil neoprene dry suit. If you get it properly sized (snug with lightweight underwear) it works perfect for 90% of the season and still swims very much like a wet suit with a lot less squeeze and air movement than a trilam. And, if you get even a serious leak on a wreck, you still have a very efficient semi-dry rather than a very wet, and very cold flooded trilam.