Both the Formosa Marine GRT 425 Tiller 2027 and the Formosa Marine SRT 635 Enclosed Centre Cabin 2026 are V-hull designs, both built in aluminium, so the buying decision usually comes down to a handful of practical questions: how many people are you putting on the water, how far do you trailer, and what does your tow vehicle weigh?
Size is the most obvious dividing line here. The Formosa Marine SRT 635 Enclosed Centre Cabin 2026 measures 21,1 feet overall (2026), giving it roughly 6,6 additional feet of deck space compared to the Formosa Marine GRT 425 Tiller 2027 at 14,5 feet (2027). Weight tells a clearer story for trailering families: the Formosa Marine SRT 635 Enclosed Centre Cabin 2026 tips the scales at 2 487 lbs - 1 770 lbs less than the Formosa Marine GRT 425 Tiller 2027 at 717 lbs. That difference is meaningful if you're working within a half-ton or three-quarter-ton truck's tow rating, especially once you factor in a motor, gear, and fuel.
The power gap is worth calling out. Rated to 225 hp, the Formosa Marine SRT 635 Enclosed Centre Cabin 2026 has a 165-hp advantage over the Formosa Marine GRT 425 Tiller 2027's 60-hp ceiling - enough to notice on acceleration and at cruising speed, particularly with a full passenger load.
For family outings this is probably the sharpest distinction between the two. The Formosa Marine SRT 635 Enclosed Centre Cabin 2026 is rated for 7 passengers, while the Formosa Marine GRT 425 Tiller 2027 caps at 4. If you're regularly pulling extended family or a group of friends onto the water, the extra seats on the Formosa Marine SRT 635 Enclosed Centre Cabin 2026 could be the deciding factor.
Bottom line: Choose the Formosa Marine SRT 635 Enclosed Centre Cabin 2026 if your priority is putting more people on the water - it handles 7 passengers and at 21,1 ft it has the deck room to back that rating up comfortably. The Formosa Marine GRT 425 Tiller 2027 is the smarter pick if you want a lighter, easier-to-trailer boat rated for 4 that costs less to run day-to-day.