In my experience, you need to be careful with having too many distributors of the same product. The company i work for is the European distributor getting X discount. We then sell to a Partner programme and they all get the same level of discount from us. It is then up to them as to how much they discount a product to gain the sale over their competitors.
As tarty hold the leading share of distribution in the UK, they will get a pretty good discount when purchasing components. If this new company starts up and competes against Tarty and taking their sales, Tarty may lose their level of discount as the value of their spend decreases. This could mean the prices going up on conponents which would be bad for you, the buyer.
The other fact is Tartybikes is now a household name. I know there are other smalled places selling some products (onza for instance), but essentially, Tarty will have the stock and be able to offer the best price.
If this new company does get set up, it will probably be running a smaller margin on products to be competitive and no business likes to do that unless you are box shifting product at a higher value. As you can see from the stress Adam gets, it could be more hassle than it's worth.
All the best to this new company, but think how the pricing could affect the UK market.