Ion list performance slow for large data

2 Questions:
1. Which state of wip, still in dev, testing?, is it ready enough to try to use and reduce that freeze time?
2. I have another ion-list inside a multiline template in a popup with 5 items, the directives item-left and item-right doesn't work there, is it fault of popup, ES6 template string or mine using ion-list in a weird context?

this_ref.showAlert({
      title: 'Cumplimiento ruta',
      template: `
      <ion-list inset>
        <ion-item>
          <p item-left>Potencial</p item>
          <p item-right>: ${potencial}</p item>
        </ion-item>
        <ion-item>
          <p item-left>Meta hoy</p item>
          <p item-right>: ${metaHoy}</p item>
        </ion-item>
        <ion-item>
          <p item-left>Ventas hoy</p item>
          <p item-right>: ${ventasHoy}</p item>
        </ion-item>
        <ion-item>
          <p item-left>Falta</p item>
          <p item-right>: ${falta}</p item>
        </ion-item>
        <ion-item>
          <p item-left>Cumplimiento</p item>
          <p item-right>: ${cumplimiento} %</p item>
        </ion-item>
      </ion-list>
      `
    })

This is the function that uses the args above to instantiate a popup:

showAlert(args) {
  this.closeDialog();
  args.title = args.title || 'Error obteniendo datos';
  args.subTitle = args.subTitle || '';
  args.template = args.template || '';
  this.dialog = true;
  return this.popup.alert({
    title: args.title,
    subTitle: args.subTitle,
    template: args.template,
    cssClass: 'alert',
    okText: 'Cerrar',
    okType: 'primary'
  });
}