8X8 or hydraulic excavator, advice please?

[Surftrucker]

Hi All, new member here. Decided to get some advice from the experts so I’ve come to this forum. Superb work here, very impressive and all credit to the contributors.
I’ve always tried to build items from scratch but struggled in recent years with family commitments etc. to get the necessary time for this approach. Consequently, I have lots of started projects but few finished. I have a Tamiya Scania with MFU and a few other bits. Now I want to invest some money into the hobby and was looking at two options:
• I have 3x high end metal driven diffs and chassis from a well-known German company, do I buy a 4th diff to complete an 8x8 set up along with the suspension and linkage elements and a good high end radio to match? (I have speed control and sound unit from Servonaut).
• Or do I purchase something like a 330D excavator as an entry into the hydraulics sector of this hobby along with a basic radio?
Both are very appealing but I’m leaning towards finishing the 8x8 and getting a good radio as a basis to build on in future years…… over to you guys…… thanks.