Oh Gawd, here we go again............
I can't imagine riding anything with 3" risers! On the dirt bikes, how do you keep your elbows out while being able to sit up close to the tank and weight the front end in turns?
Your elbows must be up by your ears! (or hanging down improperly)
Hell, yeah you can lift the front end easier (not that this is a problem on any modern trials or dirt bike). I would hope so, but you have compromised the option of being able to shift your weight to the front tremendously.
I have tried guys bikes that have risers and the front pushed so bad in turns that the bikes were IMO un-rideable.
Now.....if you are going for comfort and riding long distance, feel free to get your ergos to suit what "feels" good, but you are certainly not helping your riding any. It would be interesting to show up at one of the Trials Training Center's classes with big asssed bar risers on and see what the top instructors have to say. hmmmmm.
I've had my share of back pain and riding in the attack position seems to be the best for me. Standing straight up requires my back and lats to do too much work to keep me pulled into the bike. As usual YRMV.