My experience like 3-4 is”usable” more towards 4

7

Penetrative sex (ex anal with a trans woman) may present challenges but frotting maybe a cock sleeve, oral is all 100% doable. My best advice for trans and t4t sex is get creative. There also isn’t a book on fucking trans men that I know of and it’s a really under discussed topic tbh

5

depends on your specific anatomy etc but you can get an “extender” at that size, it basically suctions on and then use that extra length for penetration

1