I have both an Ulterra and 2 Talons. I'll give you my opinion.
Don't go with power pole. Look for a good deal on Talons. Much easier to install and they go straight down.
As far is spot lock goes....
Don't expect for spot lock to stop your boat from swinging around or to hold you on a tree vertical fishing. GPS is not accurate enough to do this. Spotlock works good for holding you still for cast and retrieve type fishing but not for situations where you need a very tight line. Spot lock works best when there is current or wind. You can setup into wind and the current or wind will help the trolling motor to stay "revved up". If it is dead calm. The trolling motor will not rev up fast enough to keep you from drifting. When you drift, it will spin up late and over compensate because it has drifted too far.
Shallow water anchors work GREAT and are perfect for staying dead still on a spot. If you have two, they will stop your boat from spinning and you NEVER know when the wind is going to shift on you. You can buy talons in 15 foot now. I have two twelve footers and LOVE them.
I bought the ulterra trying to avoid spending money on the Talons and I've discovered they really are two different things. Spotlock is just not good enough to work for me in all the situations I want to fish. It just isn't. When vertical fishing. One foot can make a difference between catching a 100 fish and not catching anything. Also, it is almost impossible to hold on a dock with just spotlock.
If I had to choose between the two, I would buy the Ulterra. Just don't expect it to do everything you want it to do. There are plenty of situation where Spotlock will not hold you where you want to be. You just can't set it and forget it. Even with the heading sensor it will not keep your boat from swinging or swapping ends under many circumstances.
Just my penny.