what kind of hp gain can realy be expected with crossover vs circ pump.

5-10hp

I like crossovers more for simplicity than for the Hp gain. It cleans up the front of the engine, gets a belt, pulley, etc. out of the way, and looks much nicer... One less thing to leak and go bad as well...

Ditto..

Any speratic temp problems,

I have only seen that on the ones running a t stat. If you run one with no t stat or just a restrictor it will run cool or just slightly warm all of the time.. There is not much to go screwy with them when you keep it basic. If you want me to price one out for you feel free to call me.. Jamie / Lakeside 570-639-2628