Yes, Mundo is full 4G/LTE, like Simyo Tuenti and Vodafone yu.
There are many other good prepaid offers in Spain, like 5GB / 10€ or 10GB / 20€. Read after "Mejor tarifa de tarjeta prepago" on the following page:
https://www.xatakamovil.com/mercado/...verano-de-2017
For those that only need data this summer, there are some summer specials (
https://www.xatakamovil.com/tag/verano-2017 ):
- Simyo one time 10 GB/30 days gift.
- Tuenti triple GB (3GB/6€, 12GB/14€).
- Orange Mundo double GB.
- Vodafone yu double GB.