I don't know which is better, or deeper, but would probably go with the F75, if I was given a choice of the two. The Racer sounded like it was the best detector ever made, for a few months, half dozen threads singing praises, then it just fizzled. There was an issue with stock coil ears breaking, but the company stepped up, made it right, replaced the coils free of charge, a quick too. Seemed like good customer service, you think it was a Garrett machine. Don't think that was the reason, several other companies released new detectors with flaws. ATPRO leaked, camlocks didn't unlock, control box fell off. CTX3030 had/has cheap seals...
I was a little tempted by the Racer, but it got over hyped before it was in stock, kind of wanted to wait and see how it worked out for all those pre-order guys, some didn't hold on to them long enough to really learn them. Figure there wasn't much difference with most any other mid-range machine, except the price...