Any opinions on Oade vs. Busman mod?
Mine's Oade modded. I went with my Oade mods for a couple reasons: <1> fairly loyal customer since I was so happy with my previous mods (modSBM-1, digi-UA5, W UA5, T+ UA5) and customer service, and <2> Busman hadn't yet sorted his arrangement with Cascade and I was willing to pay a bit more for the warranty Oade Bros offer on their work and the unit itself. First mod included ch1-2 transparent modded. Just got it back after round two which included changing ch1-2 from transparent mod to warm mod and moved to and improved on the transparent mod for ch3-4. Still haven't gotten a good feel for the W and new T mod since I just got it back, but will learn more as I record additional performances.
How are people liking their R4's?
Love my R-4. Really enjoying running 4-mic mixes. I'm able to get a sound I simply cannot from two channels (duh). I typically run 2-ch with a tighter polar pattern (typically hypers or cards, usually XY) and 2-ch with a wider polar pattern (typically subcards or omnis, usually split or NOS). Mixing the two in post gives me a very up front and direct sound (from the hypers/cards) with nice ambience and imaging (from the subcards/omnis).
Are they rugged and reliable?
It's proven very reliable for me so far. Yeah, it's plastic, and not tank-like as my previous V3, but I've encountered no problems to date. Used it in fairly serious heat at RockyGrass last year with no problems.
Is the HDD user replaceable?
I know mmmatt's done it. Not sure how I'd go about replacing the HD after getting the mods - I'd have to remove the Oade warranty sticker. Maybe best to perform the HD replacement before getting it modded, or at least check in with Oade or Busman regarding replacing the HD post-mod.