[God]

As far as I understand, BCH has raised the block size to 8mb rather than Bitcoin's 1mb blocksize.

My questions are:

What are the advantages of this? 
If BCH had the the same transaction volume of BTC right now, how well would it cope? 

What would be the downside of raising the blocksize to 8mb?
Surely there must be a drawback in doing so, otherwise, everyone would have agreed on doing this and there wouldn't be all these forks.

Thanks

[Omniscient]

BCH can handle 8 times the amount of transactions. But it doesn't have Segwit so technically if Segwit is more adopted you'd probably see 6 times more transactions. BCH doesn't have anywhere near the adaption yet so at this time there isn't a lot of advantage with the fork. More volume is with ETH than BCH.

Downsizes of the block increase are negligible. Not really going to make a difference to most people.

I wish more people used BCH to ease the BTC network but there must first be things setup a lot better.

[God]

Thank you both for your answers.
So, raising the block size is only a short term solution? And, invevitably, BCH will face the same issues as BTC is facing right now when the volume of transactions in the network increases?

Is a long term solution to the scalability issues, the Lightning Network?

Again, what are the drawbacks of introducing such thing (if any as it's only and alternative medium to send transactions though).

[minimalist]

Big blocks results in the ability for more transactions to be cleared every 10 minutes. If BCC achieves the same popularity as Bitcoin, there will still be a fee market, although transactions will be cheaper. To eliminate this, their vision is to perpetually enact block size increases, allowing more transactions to be cleared every 10 minutes.

This may make sense economically - buy a hard drive or two every year if you run your own full node; upgrade to gigabit internet - but from a technical standpoint, this bruteforce solution to scaling is stupid. Refactoring a network that scales as terribly as Bitcoin is superior. By reducing the size of transactions with segwit, the block size was essentially increased to 2MB. More transactions can fit into a segwit block than a legacy block. Transaction throughput will increase by a few orders of magnitude with LN. Schnorr signatures. Maybe a block size increase...

Keep in mind that BCC was not the first project that attempted to raise the block size. All of those proposals improve transaction throughput by a small factor. The benefits are trumped by the downsides, including miner centralization and fewer participants in the network.