I have a Bike Box Alan, a Velovault bike box and a Polaris Pod Pro.
In ascending order - the Polaris is a little more compact than the other two. It is just as sturdy, and a bit cheaper, but I was never too happy with the latches. It is also a bit tighter because of its size - it just about takes a 54cm frame without taking the mech off. That being said, it generally did the job (and if anyone wants to buy one second hand, ..... )
The other two are similar, but I prefer the Velovault model. BBA are pretty good. I can fit a 54cm frame easily without taking off the rear mech. I even leave my seat post in place. The only thing I remove are pedals, wheels and bars. Definitely no need to take off the fork! In fact, keep your stem in place when you travel, who knows what can go wrong the headset when you rebuild the bike at your destination (he says from experience). The BBA has a removable pole to provide support in the middle that can be a bit fiddly, but general the boxes do the job. Although I always use the back up of foam and bubble wrap inside.
Until recently, BBA was the best box unless you took out a mortgage and bought a Scion box. However, you now have the option of the Velovault bike box. Generally, the design is the same as BBA with one or two improvements. The latches on the outside of the box are better and less likely to flip open accidentally. The support pole has been replaced by fixed half-poles that fit together when you close the box. The wheels fit in the lid slightly better, and the Velovault has fixing straps for the wheels which the BBA doesn’t have.
Ultimately, you won’t go wrong with the BBA or the Velovault, and there is very little to separate them. Just remember that they are not perfect - even solid steel may not be enough protection from the efforts of Jet 2, BA or Ryanair baggage mishandlers!
I've seen a Bike Box Allan - it seems very well made...my only observation with it is the need to remove the forks from the bike - it does make the box shorter but it is something else to potentially rattle around and get knocked or do the knocking.
It has a metal pole in the middle of the bike to help prevent crushing - it looks very well made.
From my 2 experiences of flying with a bike, the soft shell bag was a complete success - no damage whatsoever to bag or bike. The second flight (with a hard case) had the bike dropped from the aircraft on to the tarmac - box corner was smashed and shattered and somehow, the force of the fall managed to drop my brake pads out the brake. Hole in the box was big enough to get my fist in, so glad it was only brake pads that were lost (I had spare pedals and some ot spares velcro'd to the side of the box which could have fallen out).
Needless to say, I'm a bit wary of hard boxes now (also transporting them at the other end could be a mission as they aren't small). The Bike Box Allan though seems to be very good, I'd much prefer not removing the fork, but the finish on the box looks very good and it looks like it is will do a very good job.
So far (probably 6 trips) it has done well - no damage to bike or box. She can get her road bike in without taking off Rear Mech - but that is only due to
it being a very small frame. My bikes would need that taken off as a min. we use extra padding (pipe insulation, foam etc) and it came with wheel bags
also I'm certain.
It isn't light .....but the case and her bike are just OK to go on RyanAir as a standard bag (saving £'s) - useful for your CX trips to Ireland!!!