Oceanic Excursion II Pre-Purchase Advice

I am tossing up between the Exc II and something like the probe being more traditional inflation. I have tried both on with tank and both feel good, though I like the lightness and less bulky Exc II. From reading various reviews I was interested in Excursion II owners first hand opinion on the following;

1/ I read it can ride up high at times and the optional crotch strap is recommended. I am assuming this is on the surface? Sounds like compensation for a poor design?

2/ The tank strap may not be the best design as some have experienced tanks slipping during the dive?

3/ General feedback on balance and usability

Thanks