My current audio set up is a Roland R-44 4 track audio recorder, Sennheiser MKH-416 boom mic, 2 Sennheiser and 2 Sony UHF wireless lavs, a Sony wireless handheld, K-Tek boom pole, Rode Blimp, 2 Roland R-05 recorders, and a handful of other audio gear. Anyhow, I don't normally work as a pure audio guy, but I'm thinking I'd like to expand into it and I actually have a gig coming up as a boom op/audio guy and will need to make a couple of purchases for it.

My big issue is the MKH-416 needs a lot of gain, and when I close mic interview subjects I have the gain nearly all the way up on my R-44 (obviously along with Phantom Power engaged, as well). If I'm working as a live boom op I'll have the mic further away from the subjects, and thus will have even less gain. I was originally considering getting a Porta Brace bag for my R-44 that would hold a couple of lavs, as well. However, I'm thinking maybe I should expand and get a Sound Devices 302 mixer so I can get a hotter clean boost for my boom mic . Then the question is, what recording device should I pair it with? It seems like it would be cumbersome to strap the big R-44 into a bag along with the SD 302, especially since the 302 outputs a single S/PDIF signal (or XLR if not using breakaway cable directly to camera), so I'd probably be better off getting a Tascam DR100 MK II or using one of my Roland R-05's (would the Line-In bypass the device's pre-amp?).

Stick with just the R-44 or get the 302 and pair it with a recorder, and which one?

The 302 is a mixer with only L/R outputs.
The R-44 by itself would be more convenient.

How much better are the pre-amps on the SD vs the Roland?

I ended up picking up a used 302 on eBay.

I seldom believe expensive equipment can defy the laws of physics . If 3 ft is optimal distance for the position of a shotgun mic buying the most expensive mic won't yield the same results from 6 ft. The same sort question has been ask a hundred ways.

I seldom believe expensive equipment can defy the laws of physics . If 3 ft is optimal distance for the position of a shotgun mic buying the most expensive mic won't yield the same results from 6 ft. The same sort question has been ask a hundred ways.

Yes. If you find yourself needing that much gain, then either you microphone is broken or else you are using it wrong. There is no microphone equivalent for a zoom lens. Amateurs tend to expect far more out of microphones than they are capable of.

I seldom believe expensive equipment can defy the laws of physics . If 3 ft is optimal distance for the position of a shotgun mic buying the most expensive mic won't yield the same results from 6 ft. The same sort question has been ask a hundred ways.Indeed, expensive gear (or lack thereof is no a substitute for experience/skills.

I agree with you guys, but I kept seeing people say you should have really high quality pre-amps to match mics like the 416 and that the R-44's aren't up to snuff. As with many things, paying a premium over mid-range gear a lot of times only gets you an extra 10% or so of results, so I wasn't sure if this would be the case. I guess I'll find out when I receive the 302.

FWIW, The mic preamps can't be bypassed on the R-44. A line level signal is just padded down to mic level.. as is the case with many budget recorders. Actually, I would expect better at that price.
In any case, a high-quality initial preamp helps.