While I haven't shot the 300mm f/2.8 with a 1.4X telecon, I have shot it indoors and love it. However, for outdoor shooting during hikes and climbs, I love the 400mm DO because of it's size. I've lugged it up 14,000' mountains with no issue, and gotten what are (for an amateur like me) great results. I have a well-connected friend who loans me both of these lenses from time-to-time, so I'm a lucky guy...
As for EXIF, these are all 1/800 sec and f/2.8. ISOs are 6400 for all but the "over the bar" shots, which are 3200. Our track is NOT well lit. All are with the Canon 300 f/2.8L Mk II -- an amazing lens by all measures and not that heavy at all. No monopod used--all hand-held.
No, I haven't compared the original and the Mark II 300mm f/2.8L -- just got the latter (used here) as a loaner from a VERY generous friend.
I'll suggest the Mountainsmith Borealis for anyone that wants a lot of flexibility. It's very durable, holds a tons, has a water bladder/laptop computer compartment, etc. Works well for hiking, but also doubles as a great carry-on or checked bag for travel. Has a special mount for carrying a tripod, too.
I'm going to France for two weeks (Paris, Normandy, Tours, Toulouse, Avignon, Reims) and with my 5D Mk III I'm taking the 8-15L fisheye, 17-40L, 24-105L, and 70-200 f2.8L Mk II. Might as well slip in the 40mm pancake, too.
Just got shipping confirmation from B&H for my kit. Added a protective UV filter (Hoya) and a hoodie. Arrival due this Thursday. Salivating won't stop. It'll arrive just in time for a holiday trip to northern Europe where I'll have plenty of opportunity to test it's High ISO/Low Light Performance (and probably the weather sealing, too!)
B&H just lowered the package (w/ 24-105mm) to $3599 to match Adorama, and sweetened the deal with a free extra battery and 16GB Sandisk CF card (plus some Lowepro bad I don't need). I took the plunge and will have it on Thursday. Salivating has begun.
Been trying to execute this deal for almost 24 hours and have been denied every time via PayPal. My guess is that the company is blanket denying everyone so that you have to call into them directly, at which time they cajole you (or try) into getting additional crap, warranties, etc. The $3476 for the package with the 24-105mm is a gr great deal, but I've already wasted a couple of hours trying to make this happen, so the diminishing returns are such that I'd just pulled the trigger with Adorama at $3599 and moved on, saving me hours of hassle for the relatively paltry $123. anyone want to by a 15-85mm lens?