Actually, I have 2 questions for people who work with/rode on any regional jet, especially the Canadair RJs (every other RJ's welcome too).
 After a flight to Colorado Springs (minor airport);flight back to Phoenix (major airport), I've noticed that unlike some airports...:
Photo © Jonathan Derden
...the passengers board/disembark the Canadair CRJ200 via an aerobridge.
(Of course, looking at the picture above shows the aerobridge cannot go any further towards the CRJ's entrance; it would hit and damage the stair. While boarding, I saw a metal bridge linking the gap left between the aerobridge and the entrance.)
Whilst other airports...:
Photo © Rafal Szczypek
...the built-in door/stairs are used.
My question [1(a)] is: Which/when do airports have passengers step on the tarmac, and making the passengers board from the stairs? On both my encounters, KCOS and KPHX airports use the "aerobridge+metal bridge combi" for regional jets.
[1(b)] If question 1(a)'s answer is "no airports are doing 'stair-boarding' anymore", then does European airports do that?
 Looking at this picture and Author's Information of the new CRJ-700...
Photo © Chris Liao - SPOT THIS!
...my second question is: Does the newer versions of the Canadair regional jets have to have the "aerobridge+metal bridge combi"?(look at the paragraph in small fonts above if you don't know what I mean).
[2(b)] The author discussed about the CRJ-700 being slanted and all and was wondering if Canadair saw the problem with the RJ-200 jets making airports use the "aerobridge+metal bridge combi". If yes, is it naturally slanted or does the pilot have to push a switch to lower the jet's nose?
Gotta love 'em Regional Jets!!!
(gotAirbus?)-(Got Commonality?)-(Have A Nice Flight!)