I have the LA610. What is the difference between the 710 and LA610?
The LA610 is a fantastic tube pre-amp, as is most everything I have ever heard from universal audio (including their software).
The 710 is a single channel pre with a tube stage, as well as a solid state stage. The two stage can be blended together to achieve a lot of flexibility. I have been able to get some very flat recordings, as well as some very harmonic driven recordings as well.
Vintech pre's are also a favorite of mine, if your spending a few dollars.