8 ohm subs, is this setup right?

Hello all,  I am new here and have been reading some old posts learning abit about ohms.  This made me think if the purchase I am about to make is a smart one.  Maybe you guys could give me your thoughts on it.  Right now I have a MTX 6001 mono block amp that is 300 watt rms @ 4 ohms running two JL 15w1 150 watt 4 ohm subs one off of each speaker output.  I have the option of replacing these with two Rockford P115S8  200 watt 8 ohm subs.  Those subs are my only option, they dont have any other 15 inch subs and I am not shopping around because I get them at cost+10% and if they were not that cheap I would just keep the JL's.  So would I be right  that the new 8 ohm subs run in parrallel with the amp bridge would be getting 150 watts of power to each sub @ 4 ohms?  And if so will I notice an increase in bass or will it just be cleaner bass? What do you guys think of the 8 ohm subs, are they worth getting, is there a better way to wire them to my amp (besides getting 3 or 4 of them) or am I totally wrong and have no clue what I am talking about? 

I included a little picture  hopefully it is included in the post because I dont see it in the preview.

I guess us rookies cant post picks so here is a link if you want to look.

https://i275.photobucket.com/albums/jj304/auzmoa/BothSetups.jpg

sound wise I think it would be a down grade.

The JL's are quality subs, probably comparable to the P1's, or a little better.

More importantly, the way you have it with a 4 ohm sub on each of the amps outputs the amp is seeing 2 ohms, so ~300w to each sub.  That will give you a lot more output than 1/2 the power to similar subs.

What enclosure are the JL's in? What would the RF's be in? Do you want more SQ over SPL, or the other way?I think it would be a downgrade in SQ at least. Probably output, too.

SQ; I would never consider the RF's to be a good comparison to the JL's.

SPL; The amp will give the RF's about 150watts each. The JL's are getting 300watts each, now. So, all else being equal between the two subs, the RF's would in theory put out 3dB's LESS than the JL's. -I'll explain why. The amp is internally bridged. Meaning, both pairs of outputs are connected together on the inside. It's got 2 pairs just for ease of wiring -so you don't have to cram multiple speaker wires into one terminal. That being said, no matter how you have two speakers connected to it (either one on each terminal, or both on the same), they are ran in parallel in both of your drawings. The 2 4ohm JL's are loading the amp to 2ohms (600watts RMS @ 2ohms) and the RF's would load the amp to 4ohms (300watts @ 4ohms).

I wouldn't. 2 cents spent...