Thank you for your insight & experience. I just found out Artista &Hey Ruscle. I've recently purchased 2 pairs of shoes from TLB Mallorca and one pair of shoes from Cobbler Union.
TLB: Dark Brown suede penny loafer (Martin) and Vegano Brown Double Monks (Keaton)
CU: Dark brown museum calf semi Brogue. (William III)
I've worn the double monks and semi brogue for 4 times so far and they are holding up very well. The leather on both are soft and supple to the touch. My William III broke in after the first wear and there were no discomfort whatsoever. The double monks were a little stiff at the first two wear but it has soften up.
And to answer your question....
1. Both pair are comparable in my opinion. I believe both pair have metal shank but don't take my word for it. The Artista Line is definitely the more premium line and the quality of the leather is top-notch based on my first impression in one of my local stockist. The shape is a lot sleeker and sharper than my William from CU.
2. They do not offer any resoling/re-constructing service.
3. The semi brogue that I've received from Cobbler Union was not "perfect". I'm hesitant to use the word "perfect" because I've not received any GYW shoes without any sort of minor imperfection. However, I can confidently say that Cobbler Union provides an outstanding customer service. You can read more about my first impression here. On the other hand, the welt wasn't as clean on the TLB double monks.
It boils down to your preference. Do you want something a little more sleek? Do you want real leather stiffener? Do you want a more pronounced fiddleback/beveled waist? If it's a yes then go with Artista.
But the finishing on the sole on my William III is extremely nice (aside from the "crack") and I've been finding myself reaching for that pair more often. Whichever brand you chose to go with, I can assure you that you will be getting a quality, well-made product. I strongly believe that you will not go wrong with either pair.
C. Union both use metal shanks. I also just found out that TLB has a reconditioning/re-soling service for about $200usd.
I just bought the black wholecut from TLB Artista & C. Union. I'm looking forward to trying them on & comparing them. Congrats on
finding shoes from TLB & C. Union that meet your standards. Enjoy them!