I can vouch for that, I have just started building a speedline 1/16 severn a bit of head scratching on the building of the internal parts, the plans and instructions could be a bit betters layed outbut the quality is spot on.

The Model Slipway kits make excellent models and are easily built with excellent step-by-step instructions. Great value and ideal for an average model builder.

Speedline kits are an entirely different species. You can build exhibition standard models with all the features fully working and are good value for the quality of the parts etc. However, Speedline kits require high building skills and the ability to look at a collection of parts and assemble them without detailed instructions.

I have built both Tamar kits and enjoyed the build and the challenges they each present.

You know your own skill level and from that choose the kit for you.

Remember there are other excellent kit manufacturers too.

I've heard from someone building a speedline model that the purchasing of it can be done in sections. They say which parts are needed first. You buy them. Contact for next sections,buy them etc. Spreads the pain.
Don't hold me to this, it may have been a one off.