Is freemounting easier on a uni equipped with a brake? my guess is that free
mounting would be waaaay easier with a brake. Tomorrow I will place an
order for a new 29er which offers an optional brake. At first, I was going to
option out but got to thinking that perhaps a brake would be a good thing to have. Are there other not-so-obvious reasons to make the brake a
must-have item?
Weel, what can I say: you’ll be surprised on how useless a brake can be in freemounting 
Otherwise in MUni and during long downhill with a 26-29-36 it’s proceless!
Brakes are useless of mounting, you need the uni to move under you as you mount. Brakes are great for downhill cruising where you simulate coasting to rest your legs, also good for steeper hills to increase resistance to gravity making you go too fast 
Useless for free mounting! The brake locks the wheel into a single clocked position and does not allow rotation for the mount. Oh well, proving once again there are no short cuts in unicycling. Still thinking about going ahead with the brake though.
Dan
What 29er are you looking to buy?
In April the Oracle 29er is arriving “again” and it should have the revised frame that will accomodate the biggest 29" tire (Knard 3").
It also might be worth looking at an Oregon, not sure about your intended future riding, but having a fat wheel can be fun when the trails are muddy or snowy.
I ride an Oregon and swap wheels, 26" x 65mm and a 29" x 42mm, soon to be adding a second 29" x 35mm lightweight wheel so I can have a skinny tire option. Three wheels and one uni, saves space and expense
When I first got my Coker I was using the brake to mount and it helped a lot. You can lock the wheel and effectively step up onto the uni. Later, after much advise against it, I learned to mount without the brake and now never use it to mount, unless I’m on a wierd hill situation. Just like using a pole to hold on to, or backing up against a curb to mount, it is a crutch that you will do much better when you don’t need it anymore. But yes, as incorrect as it is, the brake can help with mounting.
Nurse Ben: I was going to buy a Nimbus 29 for commuting. However UDC site says that it is out of stock. Crud. I’ve been saving for months and now it’s not available. The Lord gives me another lesson in patience. Thanks for your info on the other two-niners as I am ready for an upgrade mos def
I use my brake on my 29 when commuting when I am at a light. I hold on to a lamp post hit the brakes and step up to the uni. it allows me to get on it in a small space without doing a running mount, which is the way i usually get on my 29.
Brake can be useful for mounting in tricky situations, though you wouldn’t want to just lock the wheel from the start.
There often comes a point where you’ve gotten halfway through the mount, where you’ve got the uni vertical, the pedals horizontal, but it’s starting to roll backward before you’ve got that front foot down - then a quick squeeze on the brake is nice to hold everything stable for a moment.
But you shouldn’t need it on flat ground, and it’s tricky enough that trying to do it will probably hold you back from learning to mount properly, so I would just treat it as an advanced move, to be skipped over for now.
A brake is really nice for riding offroad on a 29" wheel, though; I would get one anyway, just not for ease of mounting.
I would definitely get a brake on a 29. I grew up on 20s and 24s but the larger wheels are great with brakes because they go fast downhill.
I use mine almost exclusively for steady braking on long downhills to save my knees and legs. It allows you to pedal at a constant slower pace and without leaning back than possible without brakes.
UDC often gets new stock in March and/or April, as do other bike manufacturers that I know. This means they might have something new soon!