Hi Chris
I also use Vectric Aspire but I am not proficient with it.
I am more biased towards viacad to do technical workshop type drawings.
With all these programs, of course there is the learning time cost.
I do presume that you are aware that there is the line drawing editor in ecabs?
I personally find it hard to use, I wish it could be tweaked some more to make it more user friendly so we could do professional drawings easily.
I estimate it would save us one hundred to five hundred hours or more of double drawing time a year (small 5 person joinery) Plus probably eliminate errors that occur because transferring to and from different software creates errors. In eCabs it live updates which helps eliminate errors.
I could be wrong but perhaps the line drawing side of eCabs works better for cookie cutter type joinery where your team gets used to what to expect,? where as if you want drawings for external type use its hard to mold for presentation, I don't know

Other users could perhaps give their perspective?.
We use viacad pro. Its a one off licence that seems to work until windows OS changes so much it doesn't work anymore. I'm on V10 which has lasted about 4 years and still works.
Also I believe with the latest release( 14 ) You can run it on 3 machines (You would need to confirm that)
I do believe that the same parent company (Punch software or broderbund ) that owns Tubo cad also owns Via cad and they are quite simialar.
I do a lot of DXFS in Viacad to import into contour in the part editor, (Contour is pretty good once you get used to it but Viacad is an added useful and flexible tool.)
I like that you can do 3d modeling in viacad as well. Viacad is more orientated along an engineering technical approach, If you want to get into pattern making projects, molding type jobs, where as Aspire originated from a sign-writing, trophy, organic modeling orientation with a engineering back end and tool pathing features a bit like Ecabs has.
Except Ecabs is built for our Thermwoods and it is just a great screen to machine solution for cabinetmakes.
Aspire was really worth the money to me as it allows you to do a lot of arty sort of stuff that you cant do in ecabs and I sometimes import models from viacad into aspire for the tool pathing capabilities, A few decent jobs and it pays for itself and it seems very stable.
We dont do any technical type drawings in aspire because we are more proficient in Viacad.
I have attached a screen shot of the sort of drawings we do. That one is one of a more detailed type of job, but we do at least a floor plan and one or two elevations generally.
Everything is drawn in one to one size. We just drag a border around the parts we want to Print or save as PDF, or turn into Jpegs to put into PDF page format in another program like MS word or one of those PDF creating programs.
Hope it helps, just my perspective, Just my two cents.