I purchased a new Ashdown Studio15 which is very light and supposedly 300 watts. It has no provision for an extension cab. Tried it out and was underwhelmed, especially when comparing to a Fender Rumble V3. Being the incorrigible tinkerer I am, I opened it up to have a looksee. The Ashdown labelled neo speaker was VERY light and is labelled 4 ohms (I checked it on a multimeter) and 150 watts!! No acoustic batting in the cab either. I lined it and tried it out again. Still underwhelming. Replaced the speaker with an Eminence Deltalite 2515 (the older model, not the Deltalite II 2515) which is rated at 300w RMS and is 8 ohms. I got it on special. Holy cow!! All of a sudden this is a very usable combo. Fat and grunty, it's turned into a tone monster. Also, I now have the option of installing an extension speaker socket, but I can't see me needing that. The Eminence added about 3 lbs to the weight but still a light combo and easy to schlep..