In July I will be doing a 9mile open water swim for a fund raiser. I have purchased the deSoto T1 bottoms 5mm, love them! My question, should I buy the 2mm vest as well? My dilemma is that I have a large chest, 50-52 depending on clothing…the sizing chart only goes to 47+ for my size. I sold my old bib john because of mobility issues. I am a strong swimmer but if this would make it easier…opinions???