Not Sure how the Type R preforms in sealed or ported, but generally, it all depends what you're after. for SPL (Loudness) usually Ported is louder cause you're using the sound waves from both the front and back, and could also get lower bass response, but that depends on the Sub.... Sealed isnt as loud, or might not get as low (depends on the sub) but it should have better Sound Quality. But normally if you want the best of both, Run Ported Tuned Low... like 25-28hz would be pretty good for SQL...
Also, depends on space... you'll have to goto alpines website and check the specs for the box size they recommend. If space is very limited then sealed box is smaller, and ported box is larger (but somtimes not by much...)
Theres lots of answers on here to you're questions but not specific for the Type R sub.