Power Sub Talk - EON518s vs LS1801NA

I am looking for a sub to pair up with my Eon 15 G2s. I want something not too expensive, under 100 lbs and that will give a good kick and it must be powered. I'm also leaning toward 18" subs.
From looking I've narrowed it down to two, but other suggestions are welcome..

1. The EON518s which has 500W of power at 129spl and has 2 XLR inputs and 2 outputs weighing in at 65lbs. Sounds like a perfect match for my use.
2. The Carvin LS1801NA which has 700W of power at 128spl 1 XLR in and out weighing in at 75lbs.

Will there really be a difference with the extra 200W with about the same spl? Anyone heard both and want to chime in?

I've heard the JBL EON-518 powered subs with the newer EON-515 tops, two of each, and they sound pretty darn good. Being front loaded, the 518 doesn't have a lot of thump, but it really fills in the bottom end nicely.

I've always been an advocate of using the same brands because generally, the engineers build them to work together. I'd recommend the JBL over the Carvin because you're already using JBL tops.

I use the Cravin and recommend it. It outperforms a 15" Mackie. The Carvin is almost the same size as the Mackie and gives a lot of bass. Not exactly chest pounding but it will give the bottom you need. For weddings it is a great sub as you will get the bass you need and more.
I am currently looking for a little more thump for school dances.