The LA series of engines has it's pros and cons...I have two and they are reliable but have very little power. The LA series have to be the best choice for a trainer type plane and I've seen a ton of them on trainers and they all perform flawlessly.
On the other hand the MVVS has to be the most powerful engine that I've owned. Have a 49 on a Shrike and what a hand full,but I love it..If you choose to go the MVVS route,you can always throttle back and you can put in on any plane that you buy in that power range.