How do SVS subwoofers compare to REL?

I'm looking for subwoofers (one or two) that have a very "tight" natural sound and are not overly boomy. In the future I hope to pair them with some Magnepan speakers. Magnepans are known for having a natural sound, and I want to compliment that.

I've been told that the REL subwoofers (e.g.,T/9i or S/3 SHO, etc., are a good match for Magnepan speakers. However, SVS subwoofers have also been recommended to me.

I don't have any background in high-end audio, so I am interested in opinions of folks here. Are SVS subwoofers considered generally as good as REL in regard to the features I'm interested in? Is either clearly superior? (I had never heard of SVS before yesterday.)

Which subwoofer size (in REL or SVS) would be a good match for a pair of Magnepan 1.7i in an 18 foot x 15 foot room (ceiling about 10 feet) with carpet on floor?

I'm looking at these so far:

REL T/9i Subwoofer about $1300
REL Acoustics S/3 SHO Subwoofer (Super High Output) about $2100
SVS SB-4000 13.5" 1200W about $1600
Any other recommendations?

Total subwoofer budget is around $2600 max. ($2000 or less would be better.)

Also, I believe it is better to buy two smaller subwoofers, compared to one larger one, right? (I'm just not sure where I would put two. Placing one is easier in this room. And I plan to connect everything with speaker wires, not wireless.)

Thanks