I'm not sure of an RC535 - unless th tubes were ell overinflated.
If we're talking about 5.3 - them It's definitely not a "flat water leisure boat" but a very sea-worthy hull arguably more sea-worthy and tougher than many larger craft.
Depending on configuration an Opti 90 will be fine....however a 100 will be "better" - more power, WOT,quicker time to plane and improved cruising performance (IMHO without an actual test). If you have rear demountable tanks, I'd say they'd have a negative efffect on performance v. a internal central tank, just from a weight distribution standpoint.
If you have a forward mounted single console & jockey, performance will be different from twin console & 4 x single jockey, and the tanks being at the stern will have less negative effect.
You pays your money & takes your choice......I'd love to know if it's really a 535.
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